A116252
n times n+2 gives the concatenation of two numbers m and m-5.
Original entry on oeis.org
80, 8156, 9800, 467346, 532653, 998000, 76450588, 99980000, 7801738414, 8593817622, 9208120792, 9999800000, 346667333466, 401461854014, 598538145985, 653332666533, 945207479452, 999998000000, 48349470735059
Offset: 1
A116254
k times k+4 gives the concatenation of two numbers m and m-5.
Original entry on oeis.org
89, 9077, 9899, 733672, 998999, 88225293, 99989999, 8900869206, 9296908810, 9604060395, 9999899999, 326666333265, 673333666732, 700730927006, 972603739725, 999998999999, 34519562953735, 39737862788836, 49917309624954, 50082690375043, 60262137211161, 65480437046262
Offset: 1
-
from itertools import count, islice
from sympy import sqrt_mod
def A116254_gen(): # generator of terms
for j in count(0):
b = 10**j
a = b*10+1
for k in sorted(sqrt_mod(-1,a,all_roots=True)):
m = (k**2+1)//a
if a*(b+4) <= k**2+1 < a*(a+3):
yield k-2
A116254_list = list(islice(A116254_gen(),40)) # Chai Wah Wu, Feb 19 2024
A116122
Numbers k such that k concatenated with k-5 gives the product of two numbers which differ by 3.
Original entry on oeis.org
92185, 1453156572932210152879253333913, 3829098407015032018435618903285, 1017438814759112270449904796121753809
Offset: 1
92185//92180 = 96012 * 96015, where // denotes concatenation.
A116241
n times n+3 gives the concatenation of two numbers m and m-7.
Original entry on oeis.org
73, 7248, 7933, 86896, 95987, 7450774, 8912861, 3546363535354546353, 4635454646463635463, 5364545353536364535, 6453636464645453645, 31993591495513432827263, 39229430087220380122375
Offset: 1
8912861 * 8912864 = 7943911//7943904, where // denotes
concatenation.
A116259
n times n+3 gives the concatenation of two numbers m and m-4.
Original entry on oeis.org
7282817, 8171727, 4550754022124826466, 5449245977875173532, 8176518705147900805, 8951999555715882882349355522888, 9861090464806791973258446431979
Offset: 1
8171727 * 8171730 = 6677714//6677710, where // denotes
concatenation.
Showing 1-5 of 5 results.